I would wager the 1.1 figure is "average path length from CDN to end user", and quite possibly weighted by bytes served.
Most of the major players in the space (Netflix, Akamai, YouTube, Facebook, etc) have boxes inside ISP networks across major metros, so the path length to reach those ISPs' users is in fact 1 assuming a cache hit, and the RTT is certainly less than 20ms.
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I would wager the 1.1 figure is "average path length from CDN to end user", and quite possibly weighted by bytes served.
Most of the major players in the space (Netflix, Akamai, YouTube, Facebook, etc) have boxes inside ISP networks across major metros, so the path length to reach those ISPs' users is in fact 1 assuming a cache hit, and the RTT is certainly less than 20ms.